How to deploy parachute after balloon pops

Hello, not sure if this is the correct forum to post this under, but anyway. I am planning on sending a gopro around 100,000 feet up. When the balloon pops, I want it to eventually open a parachute and fall down to the ground safely. Although if the parachute opens right away, it could drift miles away from the launch site. What would be the best way to make the parachute open? Thanks for your help

Staff: Mentor

Hello, not sure if this is the correct forum to post this under, but anyway. I am planning on sending a gopro around 100,000 feet up. When the balloon pops, I want it to eventually open a parachute and fall down to the ground safely. Although if the parachute opens right away, it could drift miles away from the launch site. What would be the best way to make the parachute open? Thanks for your help

If it were me, I'd use a microcontroller with a GPS module and a steerable parachute to guide the vehicle back to the launch point. Why have to drive around looking for your payload? The balloon is going to drift a lot on its own, so using a steerable parachute to glide back to the launch point only makes sense, IMO...

To the OP: don’t even consider doing what you describe until you have obtained approval and authorization from the relevant regulatory authority. In the US that would be the FAA, in the UK it would be the CAA.

Since your aerial vehicle (balloon) will be operating out of line-of-sight it will, of course, be required to carry the relevant PSR reflectors and probably anti-collision lights, too. And in most parts of the world, everything above 10,000 feet is designated category C airspace. If you’re planning to fly your vehicle in cat. C airspace, then in most countries it will be required by law to carry a mode-C transponder. And to operate the mode-C you’ll need a GPS and a barometric altimeter.

If you ignore the rules and your GoPro ends up in the engine of a commercial airliner at 38,000 feet, you’ll need a spare thirty million or so lying around to pay compensation. And if it smashes through the cockpit of an airliner flying at 500MPH, killing hundreds of people, then I wouldn’t rate your chances of avoiding prison very highly.

In short, don’t fly anything above 10,000 feet unless you know the legal and regulatory landscape. Even below 10,000 feet you can still get into trouble. For example, did you know that if your balloon passes within a 30 mile radius of a primary airport in category-B airspace you’d also be committing a criminal offense?(At least in Europe, probably the same in the US.)

Staff: Mentor

To the OP: don’t even consider doing what you describe until you have obtained approval and authorization from the relevant regulatory authority. In the US that would be the FAA, in the UK it would be the CAA.

Good point. We've had threads here before about amateur high-altitude balloon flights, but I don't remember offhand what approvals are needed. Thanks for bringing up this aspect.

If you keep you balloon/payload within the FAA exempt specs, such as payload under 6 pounds, payload under the density limit, 50 pound break force on the payload line, etc. The flight is FAA exempt and you don't need a back up cut down system, radar reflector, FAA waiver, etc. You can just fly the darn thing!

...The OP doesn't want to deploy the parachute immediately because it will drift a long way.

Maybe.
A longer decent would mean more photos or video gets taken. That would mean more options available for whatever he's using it for. Having several times more raw material to work with may be worth a longer retrieval drive.

Thanks to all who commented. I do know I will need to contact the FAA for this. But also, where I live there are roads and woods. I like what @berkeman said about being able to control the parachute. This would be very very useful. I'm not quite sure how to go about doing this though. If you can, could you send me a pm and help me figure it out? Thanks

I doubt a "steerable parachute" will make it all the way upwind, back to the lunch side, so you have to drive for miles anyway. Unless you plan to do this many times, the time you will spend on building and testing the steering will be more than the potential time saving during retrieval.

You can get a no-contract cell phone fairly cheap.
Put an app on it that will take pics or video and save to a cloud service over the cell phone network.
Put another app on it that will allow you to track it remotely.

Send it up with a balloon and parachute system. When it comes down, log on and see where it landed. If it winds up in the top of a tree or someplace inaccessible, you can still get the pics/video from the cloud service.